ML20235M763

Special Rept:On 890206,Kaman Vent Stack B Radiation Monitor RI-VG-180 Inoperable for Greater than 72 H.Monitor Inoperable Due to High Radiation Levels.Sticking Check Source Repaired

ML20235M763
Person / Time
Site:	North Anna
Issue date:	02/20/1989
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
89-090, 89-90, NUDOCS 8902280414
Download: ML20235M763 (2)

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> YInoiNIA El.ECTHIC AND POWEli COMPANY HIcnMoxu,VIHOINIA 20261 I

W. R . CA HTWRIGH T vu e.. ..n ,rebruary 20,'1989 i Neca,EAB l

United States Nuclear Regulatory Commission Serial No.89-090 Attention: Document Control Desk NAPS /DEQ/deq Washington, D.C. 20555 Docket Nos. 50-338  ;

50-339 I License Nos. NPF-4 NPF-7 ,

j Gentlemen: ,

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND_2 SPECIAL REPORT - KAMAN VENT STACK "B" RADIATION MONITOR At 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> on February 3,1989, with Units 1 and 2 at 87 and 72 percent full power (Mode 1), respectively, the Kaman Vent Stack "B" Radiation Monitor, ,

RI-VG-180, was declared inoperable. The radiation . monitor was declared l inoperable due to high indicated radiation levels which resulted when 'the '

check source remained activated following the automatic weekly operability testing. The Action Statement of Technical Specification 3.3.3.1- requires

, that the radiation monitor be returned to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or initiate the alternate method of monitoring and submit a Special Report. i Since this Action Statement expired at 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> on February 6,1989, with the radiation monitor still declared inoperable, this event is reportable pursuant to Technical Specification 6.9.2. i The Kaman Vent Stack "B" Radiation Monitor senses the radioactivity level of isotopes present in gaseous and particulate form in the effluent release path from a variety of sources. RI-VG-180 also' provides signals for local  ;

indication as well as indication, recording, and alarms in the Control Room.

At approximately 0800 hours0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br /> on February 6,1989, RI-VG-180 was inspected and the sticking check source was repaired. During the inspection it was identified that the keyboard and several light emitting diodes also needed replacement. These additional replacements were made. The radiation monitor 1 was satisfactorily tested and returned to operable status at 2125 hours0.0246 days <br />0.59 hours <br />0.00351 weeks <br />8.085625e-4 months <br /> on '

February 6, 1989.

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U This event posed no significant safety implications because the Westinghouse Vent Stack "B" Radiation Monitors, which provide radiation indication to the )

Control Room via a strip chart recorder, common alarm, alarm lights, and  !

gaseous and particulate meters, remained operable throughout this event.  !

Additionally, the Nuclear Research Corporation Radiation Monitors, which serve as a preplanned alternate monitoring method on the "B" Vent' Stack, continued to operate throughout this event as required by the Technical Specifications.

The health and safety of the general.public were not affected.

Very truly yours, W -

cW W. R. Cartwright cc: U. S. Nuclear Regulatory Commission j 101 Marietta Street, N.W. I Suite 2900 l Atlanta, GA 30323 Mr. J. L. Caldwell l NRC Senior Resident Inspector North Anna Power Station l

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